NO. 1944. NEW GENERA AND SPECIES OF STARFISHES— FISHER. 611 



tip of ray. The first 3 to 6 plates bear a similar smaller spine, spaced 

 from the lower end of the plate one-fifth to one-third width of plate. 

 Surface of plate is covered \\ath spaced squamules. Furrow spines 6 

 or 7, compressed, blunt, the median ^\^th edge to furrow; subam- 

 bulacral spines 8 or 10, much shorter, clavate, thick, pulpy, and pap- 

 illiform, in 2 series. 



The absence of a second series of superomarginal spines and of 

 naked areas on the marginal plates will separate rohustus from 

 agassizi. The inferomarginals of agassizi have a well-developed 

 ventral face, while in rohustus they form a steeply sloping side to the 

 ray when viewed from below, there being no separate ventral and 

 lateral faces. 



ASTROMESITES, new genus. 



Resembling Persephonaster and Psilaster in form, but differing 

 from them and resembling Leptychaster and Blakiaster in the arma- 

 ture of the adambulacral and mouth plates, and especially in the 

 possession of an odd interradial series of actinal intermediate plates. 

 Differing from Blakiaster in having abactinal plates compact, inde- 

 pendent, true paxillse and in having well-developed marginal fascioles. 

 Marginal plates massive, the inferomarginals with an appressed 

 comb of slender spines; superomarginals unarmed; paxillse large, 

 flat-topped, crowded; actinal intermediate plates extending in a 

 single series far along ray ; adambulacral plates with an angular furrow 

 margin bearing a divergent group of 5 to 7 spines and numerous 

 subambulacrals, as in Leptychaster; mouth plates with extensive, 

 convex surface; 3 series of crowded suborals, graded in length from 

 the straight, even furrow series of long spines, which are graduated 

 toward 2 inner teeth; no sharp-angular furrow series as in Persejjhon- 

 aster; disk small, rays stout, rather slender; actinal interradial areas 

 small, the intermediate plates extending two-thirds the length of ray. 



Type of the genus. — Astromesites compactus, new species. 



ASTROMESITES COMPACTUS, new species. 



E, = 78 mm., r=17 mm., R = 4.6 r; breadth of ray at base, 20 mm. 

 Disk small, rays narrow but stout, tapering regularly to a pointed but 

 not attenuate extremity; sides of ray fairly high, rounded; marginal 

 plates massive; interbrachial angle abruptly rounded; paxillse large, 

 crowded, with numerous, short, crowded, blunt spinelets; supero- 

 marginals unarmed; inferomarginals with lateral comb of 4 to 6 

 appressed spines; marginal fascioles rather deep, abrupt, and narrow, 

 furrow scries angular, of 5 to 7 spines; mouth plates with straight, 

 numerous, furrow series, and 3 series of suborals; interradial areas 

 small, an odd interradial series of intermediate plates, and a single 

 series far along ray; no pedicellarise. 



Type.—Cat. No. 30519, U.S.N.M. 



